/* ===== GuangShan Autos — Main Stylesheet ===== */

/* ---------- Reset & Base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: #22252D;
  background: #F7F6F2;
}

a { color: inherit; text-decoration: none; }

img { max-width: 100%; display: block; }

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Navigation ---------- */
.main-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: #1B1E26;
  border-bottom: 1px solid rgba(255,255,255,0.06);
  transition: box-shadow 0.3s ease;
}

.main-nav.scrolled {
  box-shadow: 0 2px 20px rgba(0,0,0,0.25);
}

.main-nav .nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

.nav-brand {
  font-size: 22px;
  font-weight: 700;
  color: #E8E6E0;
  letter-spacing: -0.02em;
}

.nav-brand span {
  color: #4C8BD9;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 32px;
}

.nav-links a {
  color: #B0AEA8;
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: #4C8BD9;
  transition: width 0.25s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: #E8E6E0;
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
  width: 100%;
}

.nav-cta {
  background: #4C8BD9;
  color: #FFFFFF !important;
  padding: 8px 20px;
  border-radius: 6px;
  transition: background 0.2s ease !important;
}

.nav-cta::after { display: none !important; }

.nav-cta:hover {
  background: #3D73C0 !important;
  color: #FFFFFF !important;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #E8E6E0;
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero Section ---------- */
.hero-section {
  padding: 160px 0 100px;
  background: #1B1E26;
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 700px;
  height: 700px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(76,139,217,0.12) 0%, transparent 70%);
  pointer-events: none;
}

.hero-section::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(232,145,62,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero-section .hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-block;
  background: rgba(76,139,217,0.12);
  color: #7BAFEE;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 6px 14px;
  border-radius: 20px;
  margin-bottom: 24px;
  border: 1px solid rgba(76,139,217,0.2);
}

.hero-title {
  font-size: 52px;
  font-weight: 800;
  line-height: 1.12;
  color: #E8E6E0;
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.hero-title em {
  font-style: normal;
  color: #4C8BD9;
}

.hero-desc {
  font-size: 18px;
  color: #959390;
  line-height: 1.7;
  margin-bottom: 36px;
  max-width: 480px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
}

.btn-primary {
  background: #4C8BD9;
  color: #FFFFFF;
}

.btn-primary:hover {
  background: #3D73C0;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(76,139,217,0.35);
}

.btn-outline {
  background: transparent;
  color: #E8E6E0;
  border: 2px solid #3D3F47;
}

.btn-outline:hover {
  border-color: #5A5D6B;
  background: rgba(255,255,255,0.03);
}

.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.hero-icon-block {
  width: 280px;
  height: 280px;
  background: linear-gradient(135deg, #1F2330, #242838);
  border-radius: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255,255,255,0.06);
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.hero-icon-block .icon-large {
  font-size: 80px;
  color: #4C8BD9;
}

.hero-floating {
  position: absolute;
  width: 64px;
  height: 64px;
  background: #242838;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  border: 1px solid rgba(255,255,255,0.06);
  box-shadow: 0 8px 24px rgba(0,0,0,0.25);
}

.hero-floating.tl { top: -10px; left: 20px; }
.hero-floating.br { bottom: 10px; right: -10px; color: #E8913E; }

/* ---------- Stats Section ---------- */
.stats-section {
  padding: 80px 0;
  background: #FFFFFF;
  border-bottom: 1px solid #E4E2DC;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item .stat-number {
  font-size: 44px;
  font-weight: 800;
  color: #1B1E26;
  line-height: 1.1;
  margin-bottom: 8px;
}

.stat-item .stat-number span {
  color: #4C8BD9;
}

.stat-item .stat-label {
  font-size: 14px;
  color: #5A5D6B;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ---------- Section Title ---------- */
.section-title {
  text-align: center;
  margin-bottom: 56px;
}

.section-title .section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: #4C8BD9;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.section-title h2 {
  font-size: 38px;
  font-weight: 800;
  color: #1B1E26;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 14px;
}

.section-title p {
  font-size: 17px;
  color: #5A5D6B;
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ---------- About Section ---------- */
.about-section {
  padding: 100px 0 120px;
  background: #F7F6F2;
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-visual {
  position: relative;
}

.about-card-stack {
  position: relative;
  height: 360px;
}

.about-card {
  position: absolute;
  width: 260px;
  padding: 28px;
  background: #FFFFFF;
  border-radius: 16px;
  border: 1px solid #E4E2DC;
  box-shadow: 0 4px 16px rgba(0,0,0,0.04);
}

.about-card.top {
  top: 0;
  left: 40px;
  z-index: 2;
}

.about-card.bottom {
  top: 80px;
  left: 80px;
  z-index: 1;
}

.about-card-icon {
  width: 48px;
  height: 48px;
  background: #EEF2F9;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  margin-bottom: 16px;
  color: #4C8BD9;
}

.about-card h4 {
  font-size: 18px;
  font-weight: 700;
  color: #1B1E26;
  margin-bottom: 8px;
}

.about-card p {
  font-size: 14px;
  color: #5A5D6B;
  line-height: 1.6;
}

.about-text h2 {
  font-size: 36px;
  font-weight: 800;
  color: #1B1E26;
  line-height: 1.2;
  margin-bottom: 18px;
  letter-spacing: -0.02em;
}

.about-text p {
  font-size: 16px;
  color: #5A5D6B;
  line-height: 1.75;
  margin-bottom: 16px;
}

.about-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 24px;
}

.about-feature-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.about-feature-item .af-icon {
  width: 20px;
  height: 20px;
  background: #EEF2F9;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  flex-shrink: 0;
  margin-top: 2px;
  color: #4C8BD9;
}

.about-feature-item span {
  font-size: 14px;
  color: #22252D;
  font-weight: 500;
}

/* ---------- Services Section ---------- */
.services-section {
  padding: 100px 0 120px;
  background: #1B1E26;
}

.services-section .section-title h2 { color: #E8E6E0; }
.services-section .section-title p { color: #959390; }

.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.service-card {
  background: #222632;
  border-radius: 16px;
  padding: 36px 28px;
  border: 1px solid rgba(255,255,255,0.05);
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.service-card:hover {
  transform: translateY(-4px);
  border: 1px solid rgba(76,139,217,0.3);
}

.service-card .svc-icon {
  width: 56px;
  height: 56px;
  background: rgba(76,139,217,0.1);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 20px;
  color: #4C8BD9;
  border: 1px solid rgba(76,139,217,0.15);
}

.service-card h3 {
  font-size: 20px;
  font-weight: 700;
  color: #E8E6E0;
  margin-bottom: 10px;
}

.service-card p {
  font-size: 15px;
  color: #8C8A85;
  line-height: 1.65;
  margin-bottom: 16px;
}

.service-card .svc-link {
  font-size: 14px;
  font-weight: 600;
  color: #4C8BD9;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: gap 0.2s ease;
}

.service-card .svc-link:hover { gap: 10px; }

/* ---------- Approach Section ---------- */
.approach-section {
  padding: 100px 0 60px;
  background: #FFFFFF;
}

.approach-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.approach-step {
  text-align: center;
  padding: 0 8px;
}

.approach-step .step-number {
  width: 56px;
  height: 56px;
  background: #EEF2F9;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 800;
  color: #4C8BD9;
  margin: 0 auto 20px;
}

.approach-step h3 {
  font-size: 19px;
  font-weight: 700;
  color: #1B1E26;
  margin-bottom: 8px;
}

.approach-step p {
  font-size: 15px;
  color: #5A5D6B;
  line-height: 1.65;
}

/* ---------- Contact Section ---------- */
.contact-section {
  padding: 100px 0 120px;
  background: #F7F6F2;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 60px;
  align-items: start;
}

.contact-info h2 {
  font-size: 36px;
  font-weight: 800;
  color: #1B1E26;
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.contact-info > p {
  font-size: 16px;
  color: #5A5D6B;
  line-height: 1.7;
  margin-bottom: 32px;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.contact-item .ci-icon {
  width: 44px;
  height: 44px;
  background: #EEF2F9;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
  color: #4C8BD9;
}

.contact-item h4 {
  font-size: 15px;
  font-weight: 700;
  color: #1B1E26;
  margin-bottom: 2px;
}

.contact-item p {
  font-size: 14px;
  color: #5A5D6B;
}

.contact-form {
  background: #FFFFFF;
  border-radius: 16px;
  padding: 36px 32px;
  border: 1px solid #E4E2DC;
}

.contact-form .form-group {
  margin-bottom: 18px;
}

.contact-form label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: #1B1E26;
  margin-bottom: 6px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 15px;
  border: 1px solid #E0DED8;
  border-radius: 8px;
  background: #F8F7F3;
  color: #22252D;
  font-family: inherit;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: #4C8BD9;
  box-shadow: 0 0 0 3px rgba(76,139,217,0.12);
}

.contact-form textarea {
  min-height: 120px;
  resize: vertical;
}

.contact-form .btn-primary {
  width: 100%;
  justify-content: center;
}

.form-feedback {
  margin-top: 12px;
  font-size: 14px;
  font-weight: 500;
  display: none;
}

.form-feedback.success {
  display: block;
  color: #2E7D5F;
}

.form-feedback.error {
  display: block;
  color: #C04040;
}

/* ---------- Footer ---------- */
.site-footer {
  background: #15171F;
  padding: 60px 0 28px;
  color: #8C8A85;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 44px;
}

.footer-col h3 {
  font-size: 18px;
  font-weight: 700;
  color: #E8E6E0;
  margin-bottom: 16px;
}

.footer-col p {
  font-size: 14px;
  line-height: 1.65;
  color: #8C8A85;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 14px;
  color: #8C8A85;
  transition: color 0.2s ease;
}

.footer-links a:hover { color: #4C8BD9; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.06);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  color: #636678;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- Scroll Reveal ---------- */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .hero-section .hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .hero-desc { max-width: 100%; }
  .hero-buttons { justify-content: center; }
  .hero-visual { order: -1; }
  .hero-icon-block { width: 200px; height: 200px; }
  .hero-icon-block .icon-large { font-size: 56px; }
  .hero-title { font-size: 36px; }
  .about-grid { grid-template-columns: 1fr; }
  .about-card-stack { height: 280px; }
  .about-card { width: 220px; }
  .services-grid { grid-template-columns: 1fr 1fr; }
  .approach-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
  .contact-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .section-title h2 { font-size: 30px; }
}

@media (max-width: 640px) {
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: #1B1E26;
    flex-direction: column;
    padding: 24px;
    gap: 18px;
    transform: translateY(-120%);
    opacity: 0;
    transition: transform 0.35s ease, opacity 0.35s ease;
    border-bottom: 1px solid rgba(255,255,255,0.06);
  }
  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
  }
  .nav-toggle { display: flex; }
  .services-grid { grid-template-columns: 1fr; }
  .hero-section { padding: 120px 0 60px; }
  .hero-title { font-size: 30px; }
  .hero-desc { font-size: 16px; }
  .about-text h2 { font-size: 28px; }
  .contact-info h2 { font-size: 28px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-floating { display: none; }
}